Our laboratory is interested in elucidating the molecular basis for the relationship between hypertension, insulin resistance, and obesity. In classical insulin target tissues such as muscle and fat, insulin stimulates glucose uptake primarily by causing translocation of the insulin responsive glucose transporter GLUT4 from an intracellular pool to the cell surface. Decreased sensitivity to this action of insulin (i.e., insulin resistance) plays a major role in the pathogenesis of diabetes and has been strongly correlated with hypertension and obesity. To understand the mechanisms involved in insulin-stimulated glucose transport under both normal and pathological conditions, we have developed a novel method for transient transfection of DNA into rat adipose cells in primary culture. This allows us to dissect the insulin signal transduction pathways related to GLUT4 translocation in a physiologically relevant insulin target cell. In addition, our adipose cell transfection system is useful for studying the regulation of adipose cell specific genes. We have established a collaboration with Marc Reitman's laboratory in NIDDK to study the promoter of the recently cloned ob gene (leptin, the ob gene product, is a putative satiety hormone).